I would like to introduce you to the game of chess on ice: curling.
The sport that everybody watches for a week during the winter Olympics, perhaps not realizing that it is extremely accessible and easy to get in to depending on where you live and your proximity to the nearest club.
Games are played with two teams of 4, with each player delivering 2 rocks per end (inning/frame) for a total of 16 rocks. While one player is delivering, the next two players on the same team act as sweepers and will judge the speed of the rock as it moves and relay that information to the skip; the team captain and fourth member of the team. The skip's job is to call the shots as well as watch the rock as it moves down the sheet and emphatically tell the sweepers if they need to sweep or not. The two skips also get to throw the final 4 rocks of the end which are often key to determine scoring. The last rock thrown is called the "hammer" and is a major advantage. The hammer is given to the team that did not score the previous end.
Scoring is determined by how many rocks your team has closest to the center of the "house" (the coloured rings) which is the scoring area. Each rock is worth one point no matter where in the house it sits, as long as there are no rocks from the opposing team that are closer to the center.
As a "front-end" player, ie. the first or second thrower, your job will be to set up the beginning of the end by placing early rocks in front of the house called "guards" that are used to protect rocks thrown later on used for scoring. Front end players need to be very athletic and have careful control over their heart rate. Sweeping a rock effectively is a lot more strenuous than it looks and requires balance, strength, dexterity and focus. You need to be able to judge how fast the rock moving and where it might come to a stop while simultaneously putting your entire body weight onto the head of your broom while also moving down a sheet of ice at a jogging pace without falling down. You need to be able to switch from this burst of effort into being calm and collected in order to take your turn when delivering your next rock. Front end players will need to sweep 6 rocks every end.
"Back-end" players are the third and fourth players on the team. While the third does still need to sweep 4 rocks every end, the skip does not do any sweeping unless necessary, usually in the house. These players are generally the more tactical and precise of the team, able to figure out a strategy that allows either a score of multiple points, or even to try and steal points from the opponent when they have the hammer.
Curling is generally considered to be a social sport. Competition at the club level is not taken too seriously and most people are there just to have a good time. Depending on your local customs, you can expect to join your opponents after the game for a round of drinks.
I find it to be fairly ADHD friendly, when it's my turn to throw as a front-end player I'm keyed in and focused for 60 seconds or so and then I can sort of zone out while it's my opponent's turn, and then when it's my turn to sweep I find it a great way to burn off those calories. My heart rate easily reaches 120-130 a few times per game.
I would not however want to skip a team. Having to keep my mind in the game the entire time while watching every single person making shots and trying to figure out the correct next move is mentally exhausting and better left to others. Unless maybe that's your thing, but games usually go on for 90-120 minutes.